Partial mandibulectomies are well-tolerated in dogs and often provide good to excellent cosmesis and function. They can provide a cure for patients with epulides and are a crucial component of therapy for many other oral neoplasms.

A partial mandibulectomy is a relatively easy procedure if you have the right tools and a sound knowledge of regional anatomy. Helpful tools include an oral speculum, a Freer periosteal elevator and an oscillating saw. Important structures are the inferior alveolar nerve and the mandibular alveolar artery and vein, both of which run within the mandibular canal.

Presurgical considerations

Obtain a histologic diagnosis, dental radiographs or computed tomographic scans to reveal the biologic behavior or gross extent of a lesion before determining the borders of excision. In general, one to two teeth that are rostral and caudal to the gross margins of a neoplasm should be removed to allow for a margin of normal tissue.

Figure 1: An 11-year-old Belgian Tervuren with an undifferentiated sarcoma on the mandible.

Once you've determined the amount of mandible to be removed, clip the surrounding skin and rinse the mouth with an antiseptic solution. Place the patient in the appropriate recumbent position, depending on the portion of mandible to be removed (Figure 1). Place an oral speculum between the contralateral mandibular and maxillary canines. Place one or two gauze sponges in the oropharynx to prevent blood from pooling around the endotracheal tube.

Perform a mandibular nerve block by placing the index finger of one hand into the patient's mouth and locating the most caudal aspect of the mandibular body. Insert a needle percutaneously, aiming toward the intraoral index finger, which denotes the entrance of the inferior alveolar branch of the mandibular nerve into the mandibular canal. Inject a local anesthetic agent just under the oral mucosa and continue it through the local tissues as you withdraw the needle out through the skin.

If access to the caudal mandible is necessary, perform a commissurotomy with a full-thickness incision beginning at the lip commissure and extending caudally. Judicious use of electrocautery is extremely helpful in maintaining hemostasis during commissurotomy since the maxillofacial region is particularly vascular.